Product Overview
The Emerson Bettis 585C EEI is a high-performance, double-acting electric actuator engineered for the automated operation of quarter-turn valves such as ball, plug, and butterfly valves in critical industrial applications. This actuator series is designed to deliver reliable and robust rotary motion, converting electrical power into precise mechanical torque to open, close, and modulate valve position. The “double-acting” designation, often associated with pneumatic actuators, refers here to the actuator’s internal spring pack mechanism; in the Emerson Bettis 585C EEI, it signifies a fail-safe design where two sets of springs provide the power to drive the valve to a predefined safe position (either open or closed) upon loss of electrical power or upon receiving a trip signal. This ensures process safety and compliance with safety instrumented system (SIS) requirements in industries like oil and gas, petrochemicals, and power generation.As a key product within Emerson’s comprehensive valve automation portfolio, the 585C EEI is built for durability in harsh environments. It features a sealed, corrosion-resistant housing typically rated to IP66/67 or NEMA 4X, protecting the internal gearing, motor, and spring pack from moisture, dust, and corrosive atmospheres. The actuator incorporates a powerful, thermally protected electric motor and a highly efficient worm gear set to generate high output torque in a compact footprint. The Emerson Bettis 585C EEI is equipped with advanced controls, including integral torque and position sensing switches, which allow for precise limit settings and provide protection against valve stem overload. Its modular design often allows for the integration of a variety of feedback devices (potentiometers, switches) and communication modules (e.g., for Foundation Fieldbus, PROFIBUS) to seamlessly integrate into modern distributed control systems (DCS). The value of the 585C EEI lies in its combination of assured fail-safe action, high torque output, environmental robustness, and intelligent control, making it a trusted solution for automating isolation, emergency shutdown (ESD), and critical process control valves where reliability cannot be compromised.
Technical Specifications
| Parameter Name | Parameter Value |
|---|---|
| Product Model | 585C EEI (Series designation; specific torque/speed is in suffix, e.g., 585C-EEI-060-20-00) |
| Manufacturer | Emerson (Bettis Actuator Line) |
| Product Type | Electric Quarter-Turn Actuator with Double-Acting Spring Return |
| Fail-Safe Action | Spring-return to a predefined safe position (Open or Closed) on power loss |
| Output Torque Range | Available in multiple torque classes (e.g., 60 Nm, 100 Nm, 250 Nm, etc., as per suffix) |
| Output Speed | Variable speed options (e.g., 8, 20, 40 seconds/90° as per suffix) |
| Motor Power | Three-phase or single-phase AC motor, depending on configuration |
| Supply Voltage | Common ratings: 24V DC, 110V AC, 120V AC, 220V AC, 240V AC, 480V AC |
| Enclosure Rating | Typically IP66/67, NEMA 4X (weatherproof, dust-tight, hose-proof) |
| Duty Cycle | S2 – Short time duty (typically 15 or 30 minutes), suitable for quarter-turn operation |
| Ambient Temperature Range | Standard: -20°C to 70°C (-4°F to 158°F); optional low/high-temp versions available |
| Position Indication | Mechanical position indicator, auxiliary limit switches |
| Torque Sensing | Integral torque switch for overload protection |
| Control Interface | Multi-conduit openings for power and control wiring |
| Mounting | ISO 5211 direct mounting interface to quarter-turn valves |
Main Features and Advantages
The Emerson Bettis 585C EEI electric actuator is distinguished by its highly reliable fail-safe mechanism and robust industrial construction. The core feature is its double-acting spring-return system. Unlike a single-acting spring which provides force in one direction only, the double-acting design uses two opposing spring sets. This configuration allows the actuator to be configured to drive the valve to either the fully open or fully closed position upon de-energization, with the springs providing the full rated torque for the safety stroke. This ensures a positive, guaranteed safe state without relying on external power, a critical advantage for emergency shutdown (ESD) and safety-critical applications. The actuator is designed for high cycle life, with precision-machined gearing and high-grade spring materials that maintain calibration over thousands of operations.Integration and control flexibility are significant advantages. The Emerson Bettis 585C EEI comes as a complete, self-contained package with an integrated control unit. It features independently adjustable mechanical torque and limit switches, allowing for precise setup to match the valve’s requirements and prevent damage from over-torquing. The design allows for easy field reversibility of the fail-safe action (open or closed) and rotation direction. The sealed enclosure and corrosion-resistant materials ensure long-term operation in offshore, coastal, and chemically aggressive environments. Furthermore, the actuator supports a wide range of optional feedback and communication devices, such as potentiometers for 4-20mA position feedback, solenoid valves for emergency trip, and digital protocol cards, enabling seamless integration into both legacy and modern smart factory networks. The combination of a trustworthy safety function, durable construction, precise adjustability, and communication readiness makes the 585C EEI a versatile and dependable solution for automating critical valves where safety, reliability, and low lifecycle cost are paramount.
